Re: [PATCH 2/2] ARM: dts: st: spear: fix dtbs warning on spear thermal sensor

[Krzysztof Kozlowski <krzk@kernel.org>]

On 24/03/2026 11:00, Daniel Baluta wrote:
> On 3/24/26 11:26, Krzysztof Kozlowski wrote:
>> On Mon, Mar 23, 2026 at 07:08:09PM +0530, Gopi Krishna Menon wrote:
>>> Running DTBS checks on st/spear1340-evb.dtb results in the following
>>> warning:
>>>
>>> thermal@e07008c4 (st,thermal-spear1340): Unevaluated properties are not allowed ('thermal_flags' was unexpected)
>>>   from schema $id: http://devicetree.org/schemas/thermal/st,thermal-spear1340.yaml
>> How is it possible if there is no such file?
>>
>> Did you just add new warning in patch #1 and then claim in patch #2 that
>> you fix it?
>>
>> You completely miss the point why this change is needed: how could the
>> DTS work before? It could not. And that should be your justification for
>> the patch, with explanation why it could not work.
> 
> Correct me if I'm wrong but I think there was a hidden bug here 
> 
> drivers/thermal/spear_thermal.c:spear_thermal_probe:
> 
>       if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {
> »       »       dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");                                                                                                                         
> »       »       return -EINVAL;
> »       }
> 
> So, the driver was checking for the correct property as pointed by 

Yes

> 
> bindings/thermal/spear-thermal.txt but the dts was using the wrong

No, DTS had two properties - correct one and incorrect.

> 
> property name: arch/arm/boot/dts/st/spear13xx.dtsi » » » thermal@e07008c4 { » » » » compatible = "st,thermal-spear1340"; » » » » reg = <0xe07008c4 0x4>; » » » » thermal_flags = <0x7000>; » » » }; And because this check is wrong:
> 
>       if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {
> 
> people really didn't notice it.
> 
> The check should be:
> 
>       if (!np || of_property_read_u32(np, "st,thermal-flags", &val)) {
> »       »       dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");                                                                                                                         
> »       »       return -EINVAL;
> »       }
> 
> So, this actual patch has uncovered a bug! 

Yes. Driver also has bug, so probably was never working. The point is
whatever commit is doing, the dtbs_check warning is not the
justification, because it was introduced by this patchset.

Best regards,
Krzysztof